/// <summary>
        /// 根据用户编号和是否已读标识获取该用户下的所有已读列表或未读列表
        /// </summary>
        /// <param name="userId">用户编号</param>
        /// <param name="isHasRead">bool，是否已读</param>
        /// <returns>已读或未读的实体对象列表</returns>
        public List<User_Policy> GetList(string userId, bool isHasRead)
        {
            List<User_Policy> userPolicyList = new List<User_Policy>();
            IQueryable<User_Policy> userPolicys = null;
            if (isHasRead)
            {
                // 已读列表
                userPolicys = (from userPolicy in _entityLibrary.User_Policy
                               where userPolicy.UserId == userId && userPolicy.IsReaded == true
                               group userPolicy by userPolicy.PolicyId into g
                               select new User_Policy
                               {
                                   UserId = userId,
                                   PolicyId = g.Select(userPolicy => userPolicy.PolicyId).First<Guid?>(),
                                   FirstReadDate = g.Min(userPolicy => userPolicy.FirstReadDate),
                                   LastReadDate = g.Max(userPolicy => userPolicy.FirstReadDate),
                                   IsReaded = isHasRead
                               });
            }
            else
            {
                // 已读列表
                userPolicys = from userPolicy in _entityLibrary.User_Policy
                              where userPolicy.UserId == userId && userPolicy.IsReaded == true
                              group userPolicy by userPolicy.PolicyId into g
                              select new User_Policy
                              {
                                  UserId = userId,
                                  PolicyId = g.Select(userPolicy => userPolicy.PolicyId).First<Guid?>(),
                                  FirstReadDate = g.Min(userPolicy => userPolicy.FirstReadDate),
                                  LastReadDate = g.Max(userPolicy => userPolicy.FirstReadDate),
                                  IsReaded = isHasRead
                              };
            }
            foreach (User_Policy userPolicy in userPolicys)
            {
                userPolicyList.Add(userPolicy);
            }
            return userPolicyList;
        }